Harrison Cocycles and the Group of Galois Coobjects
نویسنده
چکیده
Let H be a commutative faithfully flat Hopf algebra over a commutative ring R. We give an exact sequence describing the group of H-Galois coobjects. The other terms in the sequence are Harrison cohomology groups. This generalizes an exact sequence due to Early and Kreimer and Yokogawa. Résumé Soit H une algèbre de Hopf commutative fidèlement plate sur un anneau commutatif R. Nous étudions une suite exacte qui décrit le groupe des coobjets H-Galois. Les autres termes de la suite sont des groupes de cohomologie de Harrison. Cela généralise une suite exacte due à Early, Kreimer et Yukogawa.
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تاریخ انتشار 2001